What does Gmail Postmaster reputation data actually mean?

Gmail Postmaster Tools reputation data reflects how Gmail's systems view your sending domain and IPs based on aggregated signals. Domain reputation ranges from Bad to Low to Medium to High, indicating overall trust level. IP reputation follows similar categories.

These ratings influence filtering decisions but are not the only factor. A High reputation domain can still have individual campaigns filtered based on content or engagement. A Medium reputation domain might perform fine for engaged segments but struggle with less active subscribers.

Postmaster Tools also shows spam rates, authentication success rates, and delivery errors. The data updates daily but reflects trailing averages, so reputation changes appear gradually. Use this data to identify trends and catch problems early, but remember it shows outcomes rather than prescribing specific fixes.